Mesoporous, anti-corrosive RuO₂ thin films prepared by ultrasonic spray pyrolysis for supercapacitor application

The RuO₂ thin films are successfully synthesized by ultrasonic spray pyrolysis technique for energy storage applications. The amorphous nature of the deposit endorsed by X-ray diffraction analysis and Raman spectrum confirms the presence of E_g, A_1g, and B_2g vibration modes. The X-ray photoelectron spectroscopy findings show the existence of O, and Ru compositions and confirm the Ru⁴⁺ phase. The BET results indicate a mesoporous architecture with a specific surface area of 46 m²/g. Typically, the RT₄ (0.003 M) electrode shows 1889 F/g of specific capacitance in 0.5 M H₂SO₄ at a 2 mV/s scan rate. The outstanding chrono potential performance of RT₄ yields 65.27 Wh/Kg, 99.66 KW/Kg, and 86.42% of specific energy, power, and Coulombic efficiency, respectively. The charge transfer analysis demonstrates a small internal resistance (1.3 Ω) with a very low abate rate of corrosion ~ 0.1 (mm/year). The high value of capacitance and exceptional electrochemical behavior is ascribed to the network of uniform porous morphology with a high surface area that offers abundant electro-active sites for effective ion transportation.